Flexible maxillo-mandibular fixation device

ABSTRACT

In one embodiment, a bone fixation plate has first and second ends spaced apart along a first direction so as to define a length, and third and fourth ends spaced apart along a second direction so as to define a height that is less than the length. The plate has an inner and outer surface spaced apart along a third direction so as to define a thickness that is less than both the height and length. Openings extend from the inner surface to the outer surface along the third direction and are spaced apart along the first direction. Further, the plate has tangs that are offset from the openings with respect to the second direction, and extend out with respect to the outer surface along the third direction. The tangs are spaced apart from one another along the first direction, and are configured to receive a securement device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 14/796,394, filed Jul. 10, 2015, which is a continuation ofU.S. patent application Ser. No. 12/952,656, filed Nov. 23, 2010, nowU.S. Pat. No. 9,107,716, which claims priority to U.S. provisionalpatent application No. 61/263,542, filed Nov. 23, 2009, the disclosuresof all of which are hereby incorporated by reference as set forth intheir entirety herein.

BACKGROUND

The fixation or stabilization of the upper and lower dental occlusalarches to each other is known as intermaxillary fixation (IMF) and alsoknown as maxillo-mandibular fixation (MMF). MMF has historically beenincluded in the treatment of fracture, orthognathic, and reconstructivejaw procedures. Various methods for achieving MMF are known in the art.

Circumdental wiring techniques include metallic wires that are placedaround one or more teeth and then twisted in various methods to securethe teeth. Wires or twisted pairs of wires can form cables and betwisted to each other to stabilize the dental arch. Loops formed onmandibular teeth can be wired to loops formed around maxillary teeth inorder to stabilize the top dentition to the bottom dentition. While thematerials used in circumdental wiring are relatively inexpensive, thetechnique is tedious and time consuming. The wires also can interferewith dental hygiene.

Another conventional technique includes arch bars that are used incombination with wiring. Specifically, a metal bar is preformed tocorrespond with the curvature of the dental arch. Wires are then passedaround the teeth and over the bar, and then twisted to the bar. This isperformed at multiple locations along the bar to provide stabilityaround the dental arch. Since the bars typically have bent or formedhooks on them for securing wire, the hooks can be used for wiring theupper arch bar to the lower arch bar. Elastic bands can also be used tofix the upper arch bar to the lower arch bar. Unfortunately, thistechnique is time consuming, and interferes with dental hygiene.

Another conventional technique involves placing a plurality of screws inthe mandible or maxilla in regions that avoid the tooth roots. The screwheads may contain through holes. The screw head serves as an area aroundwhich wires may be wrapped, and the holes can facilitate the passage ofwire through the heads. Thus, wires may be secured to adjoining sets ofscrews to provide MMF. This system unfortunately suffers from a lack ofoverall structural stability which can be necessary, for instance, whenaddressing fractures around the teeth.

SUMMARY

In accordance with one embodiment, a bone fixation plate has a firstend, and a second end spaced from the first end, the bone fixation platehaving a length from the first end to the second end along a firstdirection. The bone fixation plate has a third end, and a fourth endspaced from the third end, the bone fixation plate having a height fromthe third end to the four end along a second direction, perpendicular tothe first direction, the height being less than the length. The bonefixation plate also has an inner surface configured to face bone, and anouter surface spaced from the inner surface, the bone fixation platehaving a thickness from the inner surface to the outer surface along athird direction, perpendicular to both the first and second directions.The thickness is less than both the height and the length. A pluralityof openings extend from the inner surface to the outer surface along thethird direction and are spaced apart from one another along the firstdirection. The bone fixation plate further has a plurality of tangs thatare offset from the plurality of openings with respect to the seconddirection, and extend out with respect to the outer surface along thethird direction. The plurality of tangs are spaced apart from oneanother along the first direction, and are configured to receive asecurement device.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description, isbetter understood when read in conjunction with the appended drawings.For the purpose of illustrating the maxillo-mandibular fixation deviceand related method thereof, there is shown in the drawings exemplaryembodiments; however, the maxillo-mandibular fixation device and relatedmethods are not limited to the specific embodiments and methodsdisclosed. Like reference numerals refer to corresponding partsthroughout the several embodiments of the drawings, in which:

FIG. 1 is a perspective view of a maxillo-mandibular fixation systemincluding a pair of fixation devices attached to the maxilla andmandible of a patient, and secured together;

FIG. 2A is a perspective view of a bone fixation body constructed inaccordance with one example embodiment in a neutral configuration;

FIG. 2B is a sectional elevation view of the fixation device illustratedin FIG. 2A taken along the line 2B-2B;

FIG. 3A is a front view of the fixation device illustrated in FIG. 2A inthe neutral configuration;

FIG. 3B is a front view of the fixation device illustrated in FIG. 3A,but shown in a compressed configuration;

FIG. 3C is a front elevation view of the fixation device illustrated inFIG. 3A, but shown in an expanded configuration;

FIG. 4 is a sectional elevation view of the fixation device illustratedin FIG. 2A, taken along line 4-4;

FIG. 5 is a sectional elevation view of the fixation device similar toFIG. 4, but illustrated in accordance with an alternative embodiment;

FIG. 6 is a sectional elevation view of the mandibular fixation deviceillustrated in FIG. 2A, implanted in the manner illustrated in FIG. 1,and taken along line 6-6 of FIG. 1 to show the fixation of the device tothe mandible;

FIG. 7 is a front elevation view of a bone fixation body constructed inaccordance with an alternative embodiment;

FIG. 8 is a front elevation view of a bone fixation body constructed inaccordance with another alternative embodiment; and

FIG. 9 is a front elevation view of a bone fixation body constructed inaccordance with another alternative embodiment.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

For convenience, the same or equivalent elements in the variousembodiments illustrated in the drawings have been identified with thesame reference numerals. Certain terminology is used in the followingdescription for convenience only and is not limiting. The words “right”,“left”, “upper,” and “lower” designate directions in the drawings towhich reference is made. The words “inward”, “inwardly”, “outward”,“outwardly,” “upward,” “upwardly,” “downward,” and “downwardly” refer todirections toward and away from the geometric center of the deviceand/or designated parts thereof. The terminology intended to benon-limiting includes the above-listed words, derivatives thereof andwords of similar import.

Referring initially to FIGS. 1 and 2A-B, a bone fixation, orstabilization, system 20 is configured to provide maxillo-mandibularfixation (MMF) for assisting the repairing of an injury to themaxillo-mandibular region. For instance, when the mandible 24 and/ormaxilla 26 is fractured at a fracture location 37, it is desirable tostabilize the broken bone segments by fixing or stabilizing the maxillaand the mandible relative to each other. The fixation system 20 includesa pair of fixation devices 22 and 22′, including bone fixation bodies 29and 29′, one or more fasteners 35 that attach each fixation body 29 and29′ to underlying bone, and one or more securement devices 23 thatconnect, or secure the fixation devices 22 and 22′ to each other. Thefasteners 35 can include bone screws or any other type of fastenersuitable for attaching the fixation bodies 29 and 29′ to underlyingbone. Thus, the fixation devices 22 and 22′ can be secured to themandible 24 and the maxilla 26, respectively, of a patient. The suitablesecurement device 23 can secure the fixation bodies 29 and 29′ to eachother, thereby fixing the mandible 24 and the maxilla 26 with respect torelative movement.

Specifically, each fixation body 29 and 29′ includes a respectiveplurality of flexible links 31 and 31′ extending between a respectiveplurality of longitudinally spaced interfaces 33 and 33′. Thepluralities of flexible links 31 and 31′ extend upwardly and downwardlyin an alternating pattern between the interfaces 33 and 33′, therebydefining respective pluralities of valleys 30 and 30′ and crests 32 and32′ between opposed ends of the fixation bodies 29 and 29′. Theinterfaces 33 and 33′ defined at respective valleys 30 and 30′ andcrests 32 and 32′ can be configured as connection or attachmentlocations. In the illustrated configuration, the interfaces 33 and 33′at the valleys 30 and 30′ are configured as attachment locations havingapertures 34 and 34′, respectively. The apertures 34 and 34′ can beconfigured to receive the fasteners 35. For example, the apertures 34and 34′ of the illustrated configuration are threaded so as to providescrew holes that receive fasteners 35 in the form of bone screws.Accordingly, the valleys 30 and 30′ are configured as attachmentlocations that can be attached to underlying bone, for instance via thebone screws. The interfaces 33 and 33′ at the crests 32 and 32′ areconfigured as connection, or securement locations which can be securedto each other to in turn secure the fixation devices 22 and 22′ withrespect to each other. In the illustrated configuration, the interfaces33 and 33′ at the crests 32 and 32′ are defined as securement locationshaving tangs 36 and 36′ that extend outwardly from the crests 32 and 32′in a direction generally towards and in between the immediately adjacentvalleys 30 and 30′, respectively. The tangs 36 and 36′ can be configuredto receive a securement device, for instance the securement device 23,so as to secure the tangs 36 and 36′ to each other. The securementdevice 23 can be provided as a suitable wire, elastic band, or any otheralternative securement apparatus as desired.

The mandibular and maxillo fixation devices 22 and 22′ can beidentically or substantially identically constructed from a bonefixation device 40 (see FIG. 2A), and oriented as desired when implantedinto the mandible 24 and maxilla 26 of a patient to provide the fixationdevices 22 and 22′. Thus, the vertical orientations of the fixationdevices 22 and 22′ are inverted with respect to each other in theillustrated configuration. In particular, the mandibular fixation device22 is oriented such that the plurality of crests 32 are positioned abovethe plurality of valleys 30, and the maxillo fixation device 22′ isoriented such that the plurality of crests 32′ is positioned below theplurality of valleys 30′. The maxillo-mandibular fixation system 20 willnow be described with reference to the bone fixation device 40 asillustrated in FIG. 2A.

The bone fixation device 40 is illustrated as oriented in a verticalplane defined by a longitudinal direction “L” and transverse direction“T” that is perpendicular to the longitudinal direction, and has athickness in a lateral direction “A” that is perpendicular to thelongitudinal and transverse directions L and T, respectively. The bonefixation device 40 is elongate along the longitudinal direction L beforethe fixation device 40 is curved, bent, or otherwise configured to alignwith, for instance, the mandible or maxilla prior to implantation. Thus,while the description of the bone fixation device 40 is made withreference to the illustrated configuration of the fixation device 40,the description applies equally to orientations achieved when thefixation device 40 is configured for implantation, for instance, in themaxilla or mandible of a patient.

Unless otherwise specified herein, the terms “lateral,” “longitudinal,”and “transverse” are used to describe the orthogonal directionalcomponents of the bone fixation device 40 and its components asillustrated in FIG. 2A. The terms “inner,” “outer,” and derivativesthereof with respect to a specified directional component are usedherein with respect to a given apparatus to refer to directions alongthe directional component toward and away from the center of theapparatus, respectively.

It should be appreciated that while the longitudinal and transversedirections are illustrated as extending along a vertical plane, and thatthe lateral direction is illustrated as extending along a horizontalplane, that the planes that encompass the various directions may differduring use, depending, for instance, on the desired orientation of thebone fixation device 40 when implanted in a patient. Accordingly, whilecertain directional terms are used herein to describe the bone fixationdevice 40 as illustrated merely for the purposes of clarity andconvenience, it should appreciated that these orientations may changeduring use.

Therefore, while the bone fixation device 40 is described with respectto an orientation such that its base (i.e., its valleys) is disposedbelow its crest (i.e., its crests), it can be subsequently oriented asdesired (for instance with the base disposed above the crest whenproviding the maxillo fixation device 22′) when implanted in thepatient. It should thus be understood that while the bone fixationdevice 40 is described in its illustrated orientation with reference toimplantation in the mandible 24, it can alternatively be implanted inthe maxilla 26 or any other desired bone structures that are to be fixedrelative to each other.

With continuing reference to FIG. 2A, the bone fixation device 40includes a flexible bone fixation body 42, which can also be referred toas a fixation plate or a fixation body, and a plurality of fasteners 44configured to attach the fixation body 42 to underlying bone. Thefixation body 42 is illustrated as defining opposed first and secondlongitudinally outer ends 43 and 45, respectively, and opposed inner andouter lateral surfaces 57 and 59. The inner surface 57 faces the gumsurrounding the bone structure to which the fixation body 42 isattached, and the outer surface 59 faces a direction opposite the innersurface 57. The fixation body 42 includes a plurality of sequentiallinks 46 A-E that can be integrally connected as illustrated, or canalternatively be discreetly attached to each other. The links 46A and46E define outer links, while the links 46B-D define inner linksdisposed between the outer links 46A and 46E. In one embodiment, thefixation body 42 is formed by wire electrical discharge machining (wireEDM), though the body can be formed from any alternative fabricationprocess. The fixation bodies 42 and 42′ (see FIGS. 8-9) can beconstructed from any suitable biocompatible material including but notlimited to commercially pure titanium, titanium alloy such as TAN,stainless steel, reinforced plastics, polymers such as polyether etherketone (PEEK) or PE, and the like.

As illustrated, the fixation body 42 includes five links 46A-E, thoughany number of links can be used such that reliable fixation can beachieved to a patient's mandible or maxilla, such as three links, fourlinks, or five links. Referring to FIG. 2B, the links 46A-E have arectangular cross-section that is elongate in the vertical plane definedby the transverse T and longitudinal L directions. Specifically, thelinks 46A-E include opposed elongate edges 47 and minor edges 49. Theelongate edges 47 can have any length as desired, such as about 1 mmwhile the minor edges 49 can have any length as desired, such as about0.6 mm. The links 46A-E can define a lateral thickness as desired, suchas approximately 0.6 mm in accordance with one embodiment. Of course, itmay be desirable to eliminate sharp corners or edges that could causeinjury to surrounding tissue when implanted in a patient. The size andshape of the links 46 impart flexibility to the fixation body 42,thereby allowing the fixation body 42 to assume multiple sizes, and alsoallowing for variable positioning of the fixation device 40 whenimplanted in the patient. In this regard, it should be appreciated thatthe links 46A-E can alternatively define any suitable alternativegeometric size and shape as desired. One or more of the links 46A-E canbe similarly or identically or substantially identically constructed,and will now be described with reference to the link 46B.

In particular, referring again to FIG. 2A, the link 46B includes a pairof opposed first and second side members 48 and 50. Each side memberdefines respective longitudinally inwardly curved upper ends 52 and 54and opposed longitudinally outwardly curved lower ends 56 and 58. Theupper ends 52 and 54 of the side members 48 and 50 of the link 46B arejoined at a first interface 53, so as to form a crest 51 of the fixationbody 42. The crest 51 is continuously curved about a laterally extendingaxis, such that the crest 51 presents a convex surface with respect to adownwardly directed view of the top of the fixation body 42. Of course,it should be appreciated that the crest 51 could assume any alternativeshape as defined by the upper ends 52 and 54 of the side members 48 and50, or as defined by a separate structure that joins the upper ends 52and 54, either directly or indirectly.

The side members 48 and 50 are longitudinally spaced from each other,and extend linearly so as to flare longitudinally outward from eachother along a downward direction from their respective upper ends 52 and54 to their lower ends 56 and 58 in the illustrated embodiment. Thus,the first side member 48 flares longitudinally outward toward the firstouter end 43 of the fixation body 42 in a downward direction along theside member 48. Likewise, the second side member 50 flareslongitudinally outward toward the second outer end 45 of the body in adownward direction along the side member 50. In the illustratedembodiment, the side members 48 and 50 flare equally outward withrespect to a transverse midline TM of the link 46B at a desired angle θanywhere between 0° and 90°, for instance between 0° and 45°, such asapproximately 14°.

The lower end 56 of the first side member 48 of the link 46B isconnected to the lower end 58 of the side member 50 of the adjacent link46A at a second interface 53 to form a valley 60 of the fixation body42, and the lower end 58 of the side member 50 of the link 46B isconnected to the lower end 56 of the side member 48 of the adjacent link46C at a third interface 53 to likewise form another valley 60 of thefixation body 42. The valleys 60 are continuously curved about alaterally extending axis, such that the valley presents a convex surfacewith respect to an upwardly directed view of the bottom of the fixationbody 42. Of course, it should be appreciated that the valleys couldassume any alternative shape as defined by the lower ends 56 and 58 ofthe side members 48 and 50, or as defined by a separate structure thatjoins the lower ends 56 and 58 of adjacent links, either directly orindirectly. The side members 48 and 50 of each link are integrallyconnected to the complementary side members of the adjacent links at theinterfaces 53, though they could alternatively be discreetly attached toeach other at the interfaces 53. Furthermore, the side members 48 and 50can assume any size and shape as desired that connects the crest 51 tothe valleys 60, either directly or indirectly.

The fixation body 42 can define any desired longitudinal distance, orwidth W between adjacent valleys 60, and therefore between adjacentcrests 51, such as approximately 20 mm, and any desired transverseheight H between the lower edge of the valley 60 and the upper edge ofthe crest 51, such as approximately 17.6 mm. The fixation body 42 can beconfigured such that a spatial relationship is defined between therespective crests 51 and/or valleys 60. For example, the spatialrelationship can be defined such that the width W between each of thecrests 51 and the width W between each of the valleys 60 is uniformthroughout the fixation body 42, as illustrated. Alternatively, thespatial relationship can be defined with two or more crests 51 separatedby different widths W, two or more valleys 60 separated by differentwidths W, or any combination thereof. Of course spatial relationshipswith respect to the height H between the crests 51 and the valleys 60can also be defined.

It should be appreciated that although the links 46A-E of theillustrated configuration are all the same size and shape, that one ormore, up to all of the links 46A-E of the fixation body 42 can havedifferent sizes and/or shapes, for example having different widths W,heights H, or any combination thereof. It should further be appreciatedthat the links 46A-E need not all have the same cross-section, asdefined between the elongate edges 47 and the minor edges 49. Forexample, it may be desirable to configure one or more of the links 46A-Ewith different lateral thicknesses, for instance to control thedeformation characteristics of particular links when the fixation body42 is flexed inwardly or outwardly in the longitudinal direction L, orotherwise shaped prior to implantation in a patient, as described inmore detail below. Furthermore, the cross section within an individuallink can be varied along one or more portions between its respectiveadjacent valleys 60.

It should be appreciated that the links 46A-E define an undulatingfixation body 42 shaped in a wave-form having wave segments that areproportional in number to the number of links 46. While five links 46A-Eare illustrated, the fixation body 42 can include any number of links46A-E as desired. Each link 46A-E is illustrated as defining a crest 51of the wavelike structure, and a portion of a valley 60 of one or moreadjacent wavelike structures. It should also be appreciated that thelongitudinal widths W and transverse heights H can vary between adjacentcrests and valleys. For instance, one or more of the crests 51 can havea height H greater or lesser than that of one or both of the immediatelyadjacent crests.

The side member 48 of the outer link 46A disposed at the first end 43 ofthe fixation body 42 terminates at its lower end 56, while the sidemember 50 of the outer link 46E disposed at the second end 45 of thefixation body 42 terminates at its lower end 58. Alternatively, itshould be appreciated that a half-link could be disposed at the opposedouter ends 43 and 45, such that each half-link would terminate at theirrespective upper ends 52 and 54, or at any alternative location alongtheir lengths as desired. In the illustrated embodiment, the lower end56 of the side member 48 of the outer link 46A and the lower end 58 ofthe side member 50 of the outer link 46E terminate at respective boneattachment locations 70, as will be described in more detail below.

The fixation body 42 includes a plurality of bone attachment locations70 that facilitate attachment of the fixation body to the underlyingbone. For instance, as described above, the fixation body 42 can beattached to an underlying mandible or maxilla, or any alternative bonestructure, such that a bone fracture is disposed between the opposedouter ends 43 and 45 of the fixation body 42. Accordingly, in theinstance of mandibular or maxillo fixation, when a pair of fixationbodies 42 are secured to each other in the manner described above withrespect to FIG. 1, the broken bone segments are relatively immobilizedto facilitate healing.

In the illustrated embodiment, the bone attachment locations 70 areprovided as screw holes 72 extending laterally through the fixation body42 at the respective valleys 60, though one or more alternativelyconfigured attachment locations can be provided in any suitable mannerso as to facilitate attachment of the fixation body 42 to underlyingbone. The screw holes 72 can be sized to threadedly receivecorresponding fasteners 44, provided in one embodiment as bone screws74. Specifically, referring to FIG. 6, the fixation body 42 includes abeveled inner surface 76 that defines each screw hole 72, and is sizedand shaped to receive a correspondingly beveled outer surface 78 of ascrew head 80. The beveled surface 76 is positioned such that the screwhead 80 does not protrude outwardly from the fixation body 42 when fullyseated in the screw hole 72. As illustrated, the screw head 80 is flushwith the outer surface 59 of the fixation body 42, though the screw head80 could alternatively be inwardly recessed or slightly outwardlyprotruding with respect to the outer surface 59 of the fixation body 42.

Of course, the screw hole 72 could assume one of numerousconfigurations, such that the inner surface 76 can be beveled straight,or rounded at any desired radius, for instance approximately 3.6 mm.Alternatively still, the inner surface 76 need not be beveled, and canextend laterally in a direction parallel to the outer surface of thescrew head 80. As another example, while the inner surface 76 isillustrated as smooth and flat, the inner surface 76 could alternativelybe threaded to threadedly engage corresponding threads of the screw head80, such that the screw 74 would be self-locking within the screw hole72. It should also be appreciated that the bone screws 74 can beself-drilling, or could alternatively be insertable into a pre-drilledhole as appreciated by one having ordinary skill in the art. Thefixation device 40 can further include a collar that surrounds the screwhole 72 at the inner surface 57 of the fixation body 42, such that thecollar would be disposed between the fixation body 42 and the underlyingbone structure. The collar would thus provide a stand-off that spacesthe fixation body 42 from the patient's gum when the bone screws 74 arefully inserted into the underlying bone.

As described above, the links 46A-E are constructed so as to impart aflexibility to the fixation body 42. Specifically, the fixation body canbend about a transverse axis to conform generally with dental arches ofpatients of different sizes and shapes, thereby allowing the bone screws74 to be inserted into the screw holes 72 and screwed into an underlyingmandible or maxilla, as illustrated in FIG. 1. Furthermore, referring toFIGS. 3A-C, the links 46A-E can allow the fixation body 42 to flexlongitudinally.

For instance, FIGS. 2A and 3A illustrate the fixation body 42 in aninitial relaxed, or neutral configuration, whereby the fixation body isin its as-manufactured configuration prior to inward or outward flexingalong the longitudinal direction L. In the neutral configuration, thefixation body 42 can define any longitudinal distance LI as desiredbetween the opposed longitudinally outermost edges, such asapproximately 100 mm.

However, as shown in FIG. 3B, a longitudinally inwardly directed forcecan be applied to one or more, including all, of the links 46, therebycompressing the crests 51 and/or valleys 60 and achieving a reducedlongitudinal length LR of the fixation body 42 to a distance less thanthe initial distance LI, as desired. The fixation body 42 can beconfigured such that when the length of the fixation body 42 is adjustedby longitudinal compression, the longitudinal distance, or spacingbetween the crests 51 and/or valleys 60 (i.e., the width W (FIG. 2A)between adjacent crests 51 and/or valleys 60) in the compressedconfiguration of the fixation body 42 is preserved with respect to therelaxed or neutral configuration of the fixation body 42. In other wordsthe spacing, or width W between adjacent crests 51 and/or valleys 60 ofthe fixation body 42 will be smaller after the longitudinal compression,but the crests 51 and/or valleys 60 can maintain their spatialrelationship; for instance the crests 51 can still be spaced apartequally as they were in the neutral configuration, and the and valleys60 can also be spaced apart equally as they were in the neutralconfiguration.

Additionally, as shown in FIG. 3C, a longitudinally outwardly directedforce can be applied to one or more, up to all, of the links 46, therebyextending the crests 51 and/or valleys 60 and achieving an extended, orexpanded longitudinal length LE of the fixation body 42 to a distancegreater than the initial distance LI, as desired. The fixation body 42can be configured such that when the length of the fixation body 42 isadjusted by longitudinal expansion, the longitudinal distance, orspacing between the crests 51 and/or valleys 60 (i.e., the width Wbetween adjacent crests 51 and/or valleys 60) in the expandedconfiguration of the fixation body 42 is preserved with respect to theneutral configuration of the fixation body 42. In other words thespacing, or width W between adjacent crests 51 and/or valleys 60 of thefixation body 42 will be greater after the longitudinal expansion, butthe crests 51 and/or valleys 60 can maintain their spatial relationship;for instance the crests 51 can still be spaced apart equally as theywere in the neutral configuration, and the and valleys 60 can also bespaced apart equally as they were in the neutral configuration. Itshould be appreciated that the fixation body 42 can be configured suchthat the transverse height H between the crests 51 and/or valleys 60after the fixation body 42 is compressed and/or expanded is similarlypreserved with respect to the neutral configuration of the fixation body42.

It should therefore be appreciated that the bone attachment locations 70can remain aligned with the underlying bone even as the fixation body 42is flexed longitudinally inward and/or outward. Furthermore, the boneattachment locations 70 can be aligned or substantially aligned witheach other along a longitudinal axis LA even as the fixation body 42 isflexed longitudinally inward and outward. In one embodiment, thefixation body 42 can stretch or compress lengthwise longitudinally anamount between 5% and 50% with respect to its length in the relaxedposition, for instance between 10% and 40%, and more particularlybetween 20% and 30%, and more particularly still about 23%. The fixationbody 42 can further stretch or compress height-wise transversely by anysuitable percentage with respect to its height in the relaxed position,such as between 1% and 25%, for instance between 5% and 15%, and moreparticularly about 11%. It should be appreciated that when the body 42is stretched longitudinally, the body 42 tends to shrink or compresstransversely, and vice versa. Furthermore, when the body 42 iscompressed longitudinally, the body 42 tends to stretch transversely,and vice versa.

Thus, the configuration of the fixation body 42 can be adjusted in situwhile implanting the fixation device 40 in the patient. For instance,the fixation body 42 can be sized and configured as desired based on thesize of the underlying bone segments to be fixed. Additionally, thefixation body 42 can be sized and configured to place the connectionlocations in a desired position prior to fastening the fixation body 42to underlying bone. Furthermore, the side members 48 and 50 allow thefixation body 42 to be bent or otherwise configured in the verticalplane as well, for instance, when aligning the fixation body 42 withunderlying bone. While the fixation body 42 is flexible, the continuitybetween adjacent links 46 provides sufficient stiffness when thefixation device 40 is affixed to underlying bone and attached to acomplementary fixation device in a fixation system.

It should be appreciated that the fixation body 42 can be constructed soas to allow the fixation body 42 to extend and/or compress as desired.In this regard, the fixation body 42 includes at least two side membersthat are longitudinally spaced from each other by an interface 53 thatcan expand and compress in response to expansive and compressive forces.As illustrated, the interfaces 53 are curved surfaces (e.g., the crests51 and valleys 60) whose curvature can be increased and reduced throughflexing, though the interfaces 53 can alternatively include angledconnections between the side members 48 and 50. The compressive andexpansive deformation of the fixation body 42 can be plastic, or canalternatively be elastic such that the deformed shape is retained whenthe fixation body 42 is attached to the underlying bone at theattachment locations 70. Of course, the height of the fixation body 42may increase slightly when the fixation body 42 is compressed, and maydecrease slightly when the fixation body 42 is extended.

Referring again to FIG. 2A and also to FIG. 4, the fixation device 42further includes a plurality of connection, or securement locations 82configured to facilitate connecting, or securing together a pair offixation devices 40 that are inversely oriented, for instance whenimplanted in a mandible and maxilla, respectively. In the illustratedconfiguration, the securement locations 82 are disposed at thelongitudinal midpoint, or apex of the crest 51 of each of the links46A-E. However, it should be appreciated that alternatively, thesecurement locations 82 can be disposed anywhere on the fixation body 42as desired. The securement locations 82 can be configured to allow asecurement member, such as the securement member 23 described above withrespect to FIG. 1, to connect a pair of fixation bodies 42 to each otherso as to restrict relative movement of the bone underlying the connectedfixation bodies 42.

The securement locations 82 are provided in the illustrated embodimentas tangs 84 extending down from the apex of each crest 51 of thefixation body 42. Otherwise stated, the tangs 84 extend in a generallytransverse direction from the crest 51 toward a longitudinal axis LAthat extends through the screw holes 72. One or more, up to all, of thetangs 84 can also include longitudinally or laterally extending segmentsas well, if desired. For instance, in the illustrated embodiment, eachof the tangs 84 includes a first segment 86 that extends transverselydown from the transverse inner edge of the apex of the crest 51. Asecond, or spacer segment 88 extends transversely downward and laterallyoutward from the lower end of the first segment 86. A third segment 90extends transversely downward from the lower and laterally outer end ofthe spacer segment 88.

Thus, a securement device, such as the securement device 23 describedabove, can engage the lower surface of the spacer segment 88 andlaterally inner surface of the third segment 90 when fixing orstabilizing a pair of mandibular and maxillo fixation bodies 42 to eachother. Alternatively or additionally, the securement device 23 canengage the laterally inner surface of the first segment 86 and thelaterally outer surface of the crest 51. For instance, a wire can bewrapped around the tang 84 and/or link 46. Alternatively oradditionally, an elastic band can be seated at one end between the tang84 and the crest 51. Because securement devices 23 can be attached atmultiple locations along the length of the fixation body 42, theresulting forces associated with coupling the securement devices 23 to acomplementary fixation body 42 distributes the resulting forcessubstantially equally across the length of the fixation body 42.

Alternatively, referring now to FIG. 5, one or more, up to all, of thetangs 84′ can include a single segment 86′ constructed similarly withrespect to the segment 86, thus extending vertically down from the crest51 in the manner describe above. Thus the tang 84′ does not include anylateral or longitudinal directional components. The securement device 23can be wrapped around the segment 86′ in the case of a wire, forinstance, or can be seated between the segment 86′ and the crest 51 inthe case of an elastic band. Alternatively still, it should beappreciated that the securement locations 82 can include the crest 51itself, without any tangs 84 or other additional structure. Forinstance, a plurality of elastic bands could be slid along the wavelikeform of the fixation body 42 to locations at respective crests 51 priorto implantation of the fixation body 42 into underlying bone.Alternatively, a wire could be wrapped around the crests 51 of opposedfixation bodies 51 prior to or after implantation of the fixation bodies42. Alternatively still, the securement location 82 could be provided asan aperture extending laterally through the links 46A-E, for instance attheir crests 51.

The fixation device 40 was illustrated and described above in accordancewith one embodiment, it being appreciated that numerous alternativeembodiments are contemplated.

For instance, referring to now FIG. 7, the fixation body can includeauxiliary links, and can alternatively or additionally includesecurement locations that are positioned differently than the securementlocations 82 described above. As illustrated in FIG. 7, the fixationbody 42 can include auxiliary links 92 connected between adjacent links46. The auxiliary links 92 can extend between the first and second sidemembers 48 and 50 of adjacent links 46 at any respective desiredlocations along the first and second side members 48 and 50,respectively. For instance, in the illustrated embodiment, the auxiliarylinks 92 extend between the first and second side members 48 and 50 atlocations proximate to, or at, the respective upper ends 52 and 54 ofthe first and second side members 48 and 50. The auxiliary links 92 areillustrated as extending transversely upward and inward from the sidemembers 48 and 50 toward an auxiliary crest 94 that is shapedsubstantially as described above with respect to the crests 51. Thus,the auxiliary crest 94 presents a convex surface with respect to adownwardly directed view of the top of the fixation body 42, though theauxiliary crest 94 could assume any alternative shape as desired. Theauxiliary crests 94 allow the auxiliary links 92 to expand and contractas described above with respect to FIGS. 3A-C, though the auxiliarylinks 92 can be configured to add an amount of stiffness to the fixationbody 42 with respect to the fixation body 42 as illustrated in FIG. 2Awithout the auxiliary links 92. The auxiliary crests 94 can bepositioned longitudinally midway between the crests 51 of the links46A-E, which can be referred to as “primary” links 46A-E when thefixation body 42 includes the auxiliary links 92.

As illustrated in FIG. 7, one or more, up to all of the auxiliary links92 can be configured as auxiliary securement locations 96, constructeddifferently or as described above with respect to the securementlocations 82. The auxiliary securement locations 96 can be providedanywhere along the auxiliary links 92, such as at the apexes of theauxiliary crests 94. Thus, for instance, the auxiliary securementlocations 96 can be configured to allow a securement member, such as thesecurement member 23 described above with respect to FIG. 1, to connecta pair of fixation bodies 42 to each other so as to restrict relativemovement of the bone underlying the connected fixation bodies 42. In theillustrated embodiment, the auxiliary securement locations 96 areprovided as tangs 98 that extend from the auxiliary crests 94 asdescribed above with respect to tangs 84 and 84′ extending fromrespective crests 51. It should be appreciated that the auxiliarysecurement locations 96 can be provided in addition to the securementlocations 82, as an alternative to the securement locations 82, or thatany combination of the securement locations 82 and/or the auxiliarysecurement locations 96 can be provided as desired.

Referring now to FIG. 8, a portion of a fixation body 42′ is illustratedas including a plurality of links 46′ that are shaped differently withrespect to the straight side members 48 and 50 of the links 46A-Eillustrated in FIG. 2A. For instance, as illustrated, the side members48′ and 50′ of a given link 46′ can be longitudinally inwardly curvedtoward each other from their respective lower end 56′ and 58′ near theirrespective valleys 60′ in a transverse upward direction along the sidemembers 48′ and 50′ toward the crest 51′, then longitudinally curvedoutwardly away from each other in a continuing transverse upwarddirection, and finally longitudinally curved inwardly toward each otheragain at the respective upper ends 52′ and 54′ of the side members 48′and 50′ near the crest 51′. It should be appreciated that theillustrated curvature of the side members 48′ and 50′ is an example ofalternative curvature for the links 46′, and that the side members 48′and 50′ can be configured with any other alternative curvature asdesired. It should further be appreciated that the fixation body 42 of afixation device 40 can be configured entirely of links 46′, therebyproviding a fixation body 42′, or can be configured with any combinationof the links 46′ and the links 46 as described above with reference toFIGS. 2A-B, as desired. The curved side members 48′ and 50′ can beconfigured to allow the fixation body 42′ to flex in the transversedirection. Accordingly, when a pair of fixation devices 40 havingfixation bodies 42′ are secured to each other as illustrated in FIG. 1,the fixation devices 40 can flex toward each other in response to theforces applied by the securement device 23. It should be appreciatedthat the fixation body 42′ can further include auxiliary links and/orauxiliary securement locations as described above with reference to FIG.7.

Furthermore, as described above, the lower end 56 of the side member 48of the outer link 46A and the lower end 58 of the side member 50 of theouter link 46E terminate at respective bone attachment locations 70, asillustrated in FIG. 2A. Accordingly, as illustrated in FIG. 2A, the bonefixation device 40 can terminate at outermost bone attachment locations70. Alternatively, as illustrated in FIG. 9, in which the bone fixationdevice 40′ includes three links 46A′-C′, the outermost links 46A′ and46C′ are attached to outermost securement locations 82′ via arms 50″ and48″, respectively. The arms 50″ and 48″ extend longitudinally outwardlyfrom the ends 43′ and 45′ of the fixation body 42′, between lower armends 56″ and 58″ and upper arm ends 52″ and 54″, respectively. However,it should be appreciated that the bone fixation device 40′ asillustrated in FIG. 9 could be constructed as described above withreference to FIG. 2A, or any alternative embodiments described herein.Thus, the outermost securement locations 82′ are disposed longitudinallyoutward with respect to the outermost bone attachment locations 70′. Asillustrated, the fixation body 42′ can include four bone attachmentlocations 70′ as illustrated, or any alternative number of boneattachment locations 70′ as desired. The outermost securement locations82′ can be disposed above, below, or at a transverse heightsubstantially equal to that of the other securement locations 82′ of thebone fixation device 40′. In the illustrated embodiment, the outermostsecurement locations 82′ are disposed at a transverse height below thatof the other securement locations 82′ of the bone fixation device 40′.

The outermost securement locations 82′ can be provided as hooks 83′extending in the longitudinal-transverse plane, or any alternative planeas desired, for example from the upper arm ends 52″ and 54″ of the arms50″ and 48″, respectively. Thus, a securement device, such as device 23described above, can engage the hooks 83′ of opposed fixation bodies 42′when fixing or securing a pair of mandibular and maxillo fixation bodies42′ to each other. In this regard, it should be appreciated that any ofthe securement locations described herein could comprise hooks or anyalternative structure suitable for connecting, or securing a pair offixation devices as described above.

Thus, it should be appreciated that fixation bodies can be provided inaccordance with multiple embodiments. Therefore, a kit can be providedthat includes a plurality of fixation devices, or portions thereof,including fixation bodies constructed in accordance with all or aportion of any of the embodiments described herein. For example, the kitcan include one or more fixation bodies 42 or 42′, having differentnumbers of links, different dimensions, such as overall length, linkwidth, height, and lateral thickness, and differently configured links(for instance differently configured side members 48, 48′, 50, and 50′,securement locations 82, 82′, and 96, and/or auxiliary links 92).Therefore, the fixation bodies in a kit can have one or more varyingcharacteristic such as size and/or shape. For instance, a first kit canbe provided having one or more fixation bodies whose components, forinstance the links and/or the securement locations, are of a first sizeor shape, and other fixation bodies whose components are of a secondsize or shape different than the first size or shape. Thus, the kit canaccommodate multiple maxillo-mandibular fixation procedures involvingsubstantial anatomical variability.

According to another embodiment, methods are provided for implanting thevarious embodiments of the fixation device 40. Generally, the methodsinclude the steps of adjusting an orientation (e.g., directional orangular) of the fixation device 40 depending on the anatomy of theunderlying bone structure. For instance, a maxillo fixation device willbe vertically inverted with respect a mandibular fixation device. It isto be understood that certain steps of the methods described herein canbe omitted, combined, performed simultaneously, or performed in adifferent order. In this regard, it should be appreciated that themaxillo-mandibular fixation devices of the type described above can beprovided as a kit that is configured to be implemented for the purposesof maxillo-mandibular fixation using the methods described below.

According to one method of providing fixation to a bone or bone segmentsof a mandible, a first fixation device such as the fixation device 40may be adapted by imparting a curvature as desired to correspond to thedental arch. The fixation device 40 can further be extended orcompressed in the longitudinal direction and/or the transverse directionto align the screw holes 72 with a desired fixation location on theunderlying bone. Thus the configuration of the fixation body 42 may beadapted to achieve the proper shape and fit for a bone fixation. Thefixation body 42 can then be implanted by inserting the fasteners 44into the underlying bone.

Next, a second fixation device 40 can be implanted in a second bonestructure that is to be fixed with respect to the bone structure thatunderlies the first fixation body 40. For instance, a second fixationbody 42 can be implanted into the maxilla in the manner described above,but in an orientation that is vertically inverse with respect to thefirst fixation device 40. It should be appreciated that either the firstand/or second fixation device is implanted over a fracture such that thedevice(s) attach a first bone segment to a second bone segment that hasbeen fractured from the first bone segment.

Once the first and second fixation bodies are implanted into theunderlying bone structure, the securement devices 23 are attached to thesecurement locations of the first and second fixation bodies. In apreferred embodiment, the securement devices 23 are attached between twovertically aligned, or substantially aligned, crests 51. It should beappreciated that the crests 51 of each fixation body can define theshortest vertical distance between the fixation bodies 40, therebyallowing for a securement device 23 that has a short length between thefixation bodies 40.

The illustrated embodiments are directed to a bone fixation system thatmay be implanted to assist in repairing a fractured bone. The fixationsystem has particular utility as mandibular or maxillo fixation system,which benefits from accurate anatomical shape and fit.

The foregoing description is provided for the purpose of explanation andis not to be construed as limiting the invention. While variousembodiments have been described with reference to preferred embodimentsor preferred methods, it is understood that the words which have beenused herein are words of description and illustration, rather than wordsof limitation. Furthermore, although the embodiments have been describedherein with reference to particular structure, methods, and embodiments,the invention is not intended to be limited to the particulars disclosedherein. Moreover, any of the embodiments described above can incorporateany structures or features of any of the other embodiments describedabove, as desired. Those skilled in the relevant art, having the benefitof the teachings of this specification, may effect numerousmodifications to the invention as described herein, and changes may bemade without departing from the spirit and scope of the invention asdefined by the appended claims.

What is claimed:
 1. A bone fixation plate comprising: a first end, and asecond end spaced from the first end, the bone fixation plate having alength from the first end to the second end along a first direction; athird end, and a fourth end spaced from the third end, the bone fixationplate having a height from the third end to the fourth end along asecond direction, perpendicular to the first direction, the height beingless than the length; an inner surface configured to face bone, and anouter surface spaced from the inner surface, the bone fixation platehaving a thickness from the inner surface to the outer surface along athird direction, perpendicular to both the first and second directions,the thickness being less than both the height and the length, wherein aplurality of openings extend from the inner surface to the outer surfacealong the third direction and are spaced apart from one another alongthe first direction; a plurality of pairs of side members, each pairbeing joined at a first interface and extending away from one another oneither side of a respective one of the openings such that the sidemembers of each pair are spaced from one another along the firstdirection; and a plurality of tangs that are offset from the pluralityof openings with respect to the second direction, and extend out withrespect to the outer surface along the third direction, wherein theplurality of tangs are spaced apart from one another along the firstdirection, and are configured to receive a securement device.
 2. Thebone fixation plate of claim 1, wherein each of the plurality of tangsincludes a spacer segment that extends outward with respect to the outersurface and further includes a segment that extends from the spacersegment and that is offset from the outer surface with respect to thethird direction.
 3. The bone fixation plate of claim 2, wherein the bonefixation plate is configured to receive the securement device between aninner surface of the segment of the tang and the outer surface of thebone fixation plate.
 4. The bone fixation plate of claim 2, wherein thespacer segment extends along a direction that has a directionalcomponent in the third direction.
 5. The bone fixation plate of claim 2,wherein the bone fixation plate includes a plurality of beveled innersurfaces, each defining an opening of the plurality of openings.
 6. Thebone fixation plate of claim 1, wherein the plurality of tangs includesat least one tang that is aligned with one of the openings of theplurality of openings along the third direction.
 7. The bone fixationplate of claim 1, wherein the plurality of tangs includes multiple tangsthat are each aligned with a different opening of the plurality ofopenings along the third direction.
 8. The bone fixation plate of claim1, wherein the bone fixation plate is bendable about an axis thatextends along the second direction so as to conform the bone fixationplate with a curvature of a dental arch.
 9. The bone fixation plate ofclaim 1, wherein the segment of the tang extends from the spacer segmentalong a direction that has a directional component in the seconddirection.
 10. A bone fixation system configured to attach to underlyingfirst and second bones, the bone fixation system comprising: a firstbone fixation plate; and a second bone fixation plate, each of the firstand bone fixation plates having: a first end and a second end that isspaced from the first end along a first direction; a third end, and afourth end spaced from the third end along a second direction,perpendicular to the first direction; a first inner surface configuredto face the first bone, and a first outer surface spaced from the firstinner surface along a third direction, perpendicular to both the firstand second directions, wherein a plurality of openings extend from theinner surface to the outer surface along the third direction and arespaced apart from one another along the first direction; and a pluralityof tangs that are 1) spaced apart along the first direction, and 2)extend out from the outer surface along the third direction, wherein allof the tangs of the first and second bone plates are each aligned with arespective one of the openings along the second direction, and the tangsof the first and second bone plate are configured to receive arespective securement device to attach the first bone fixation plate tothe second bone fixation plate.
 11. The bone fixation system of claim10, wherein the tangs of the first and second bone fixation plates areconfigured such that, when the first and second bone fixation plates areattached to the first and second bones, respectively, the tangs of thefirst bone fixation plate extend away from the second bone fixationplate, and the tangs of the second bone fixation plate extend away fromthe first bone fixation plate.
 12. The bone fixation system of claim 11,wherein each of the plurality of tangs includes a spacer segment thatextends outward with respect to the outer surface and further includes asegment that extends from the spacer segment and that is offset from theouter surface with respect to the third direction.
 13. The bone fixationsystem of claim 10, further comprising the securement device.
 14. Thebone fixation system of claim 10, further comprising a plurality of bonefasteners configured to extend through the plurality of openings of thefirst bone fixation plate to attach the first bone fixation plate to thefirst bone and a plurality of bone fasteners configured to extendthrough the plurality of openings of the second bone fixation plate toattach the second bone fixation plate to the second bone.
 15. The bonefixation system of claim 10, wherein the plurality of openings of thefirst bone fixation plate are offset from the plurality of tangs of thefirst bone plate along the second direction, and the plurality ofopenings of the second bone fixation plate are offset from the pluralityof tangs of the second bone fixation plate along the second direction.16. The bone fixation system of claim 10, wherein the first plurality oftangs includes multiple tangs that are each aligned with a differentopening of the plurality of openings of the first bone fixation platealong the second direction, and the second plurality of tangs includesmultiple tangs that are each aligned with a different opening of theplurality of openings of the second bone fixation plate along the seconddirection.
 17. A method of attaching a bone fixation system tounderlying first and second bones, the method comprising: aligning abody of a first bone fixation plate with the first bone such that firstand second ends of the first bone fixation plate are spaced from oneanother along a first direction, third and fourth ends of the first bonefixation plate are spaced from one another along a second direction,perpendicular to the first direction, and an inner surface of the firstbone fixation plate faces the first bone along a third direction,perpendicular to both the first and second directions, the first bonefixation plate including a plurality of tangs that are spaced from oneanother along the first direction and that extend from an edge of theplate body at the fourth end; inserting a plurality of fasteners into aplurality of openings that extend through the first bone fixation platealong the third direction so as to fix the first bone fixation plate tothe first bone, the plurality of openings of the first bone fixationplate being spaced apart from one another along the first direction suchthat all of the tangs of the first bone plate are each aligned with arespective one of the openings along the second direction; aligning asecond bone fixation plate with the second bone such that first andsecond ends of the second bone fixation plate are spaced from oneanother along the first direction, third and fourth ends of the secondbone fixation plate are spaced from one another along the seconddirection, and an inner surface of the second bone fixation plate facesthe second bone along the third direction; inserting a plurality offasteners into a plurality of openings that extend through the secondbone fixation plate along the third direction so as to fix the secondbone fixation plate to the second bone, the plurality of openings of thesecond bone fixation plate being spaced apart from one another along thefirst direction; and attaching a securement device to both a first tangof the first bone fixation plate and a first tang of the second bonefixation plate so as to attach the first bone fixation plate to thesecond bone fixation plate.
 18. The method of claim 17, wherein thesecurement device defines one of a closed loop and a wire.
 19. Themethod of claim 17, wherein aligning a second bone fixation platecomprises aligning the first tang of the second bone fixation plate withthe first tang of the first bone fixation plate along the seconddirection.
 20. The method of claim 17, wherein the step of attachingcomprises receiving the securement device behind the first tang of thefirst bone fixation plate along a direction that extends toward thesecond bone fixation plate, and receiving the securement device behindthe first tang of the second bone fixation plate along a direction thatextends toward the first bone fixation plate.
 21. The bone fixationplate of claim 1, comprising a plate body that defines the third andfourth ends, wherein each tang extends from an edge of the plate body atthe fourth end such that each tang is not aligned with the plate bodyalong the third direction.